C. Baud et al., PARTIAL CHARACTERIZATION OF A NOVEL CARDIOINHIBITORY PEPTIDE FROM THEBRAIN OF THE SNAIL HELIX-ASPERSA, Cellular and molecular neurobiology, 18(4), 1998, pp. 413-424
1. We report the isolation of a peptide from the brain of the snail He
lix aspersa by radioimmunoassay using an antisomatostatin. 2. The sequ
encing of an immunopositive fraction showed the presence of a new trid
ecapeptide, termed Helix cardioinhibitory peptide (HCIP), with the fol
lowing primary structure: e-Gln-Asn-Gln-Phe-Lys-Gly-lle-Gln-Gly-Arg-Ph
e-NH2. It is structurally related to the Achatina cardioexcitatory pep
tide (ACEP-1) and the terminal-amino acid sequence of HCIP is identica
l to that of FMRFamide family peptides. 3. The synthetic HCIP was test
ed on heart and neuronal activities and it was found to have inhibitor
y actions not only on the ventricle but also on visceral neurons of th
e central nervous system of Helix. Immunocytochemical investigation in
dicates its presence in visceral and parietal ganglia, in which cells
taking part in the regulation of the heartbeat have been previously id
entified.